Three Cases of Atypical Breast Metastasis from Lung Adenocarcinoma

Abstract

Metastatic disease to the breast is rare. Melanoma and lymphoma are the most common primary tumors metastasizing to the breast, and breast metastasis from a primary lung neoplasm is uncommon. It can be difficult to distinguish metastatic disease from primary breast cancer clinically. Immunohistochemistry, combined with further diagnostic imaging, play important roles in identifying the primary origin of the malignancy. An accurate diagnosis is imperative for therapeutic planning, and further workup should be considered for unusual cytological patterns. In this report, three cases of pulmonary metastasis to the breast with atypical clinical presentations are presented and discussed.

Keywords: Breast metastasis; Extra-mammary neoplasm; Lung cancer.

Figure 1.

1.4 × 1.3 × 1.3 cm irregular hypoechoic mass with irregular margins below the inframammary.

Figure 2.

Large anteriosuperior hilar mass abutting the mediastinum and encasing the bronchovascular structures to the left upper lobe. Mass at inframammary crease noted as 1.6 cm subcutaneous nodule (red arrow).

Figure 3.

(a) Mediolateral oblique and (b) craniocaudal view demonstrating multiple irregular high density masses in the right breast at 6 o’clock, 10 o’clock, and 11 o’clock. (c) Mediolateral oblique and (d) craniocaudal view demonstrating irregular masses at 11 o’clock and 1 o’clock in the left breast.

Figure 4.

(Positron emission tomography/computed tomography with extensive disease including but not limited to large right perihilar mass, multiple lesions in the breasts bilaterally, abnormal right thyroid lobe region, and multiple mesenteric and skeletal metastasis.

Figure 5.

Small widely metastatic lesions in the brain on MRI.

Figure 6.

Computed tomography of the chest demonstrating a destructive soft tissue mass in the lateral left 7^th rib measuring 5.9 × 5.8 × 4.2 cm. 1.3 cm left breast mass (red arrow).

Figure 7.

Craniocaudal view of left breast with a 2 cm irregular mass at 9 o’clock.

Figure 8.

Magnetic resonance imaging of the brain showing a solitary metastasis involving right frontal lobe.

Figure 9.

Computed tomography of the chest (a & b) with disease progression and left chest wall mass now measuring 9.5 × 5.3 cm and left breast mass now 2.4 × 2.3 cm (from 1.3 × 1.2cm). (c) Magnetic resonance imaging of the brain with interval enlargement of the right frontal enhancing lesion, 0.9 × 1 cm (was 0.6 cm).